Several technologies exist for electronically collecting images. A common electronic imaging technique is the use of a television camera to collect visible optical wavelength images that become electronic signals that can be processed and stored. This type of imaging is inexpensive, can record color and can have high image resolution. However, such imaging has severe limitations under adverse conditions such as darkness, haze, dust, and clouds. It is often very important in military applications to be able to obtain an image of targets under such adverse conditions.
Another type of image collection has been developed using infrared radiation. Infrared detectors can collect images at wavelengths that can pass through optical barriers such as haze and smoke and can also produce images during hours of darkness. The technology of infrared imaging has been developed such that relatively high resolution images can be collected and such images can be collected which have multiple wavelengths that correspond to colors within the visible optical band. Infrared imaging suffers performance degradation when thermal contrast is low, such as during a rain storm.
A still further technology for imaging is termed LADAR. This stands for laser detection and ranging. This technology uses a laser that generates very short pulses of laser light. The travel time of the laser pulse from the laser to the target and back to a detector can be measured. This makes possible the determination of the range from the laser to the target. While LADAR imaging can be quite effective, it has limitations as well.
Therefore, there exists a need for a sensor assembly with improved image collection capabilities under adverse conditions where the detected image can provide as much information as possible about potential targets in the field of the image.